The present invention relates generally to systems and methods of targeting. For example, the present invention may be used to target areas residing behind a surface.
In the prior art, U.S. Pat. No. 5,320,111 and U.S. Pat. No. 5,316,014 disclose a method and apparatus for locating and guiding a biopsy needle with respect to an X-rayed specimen having a tumor to be engaged by the needle. Intersecting laser beams are utilized to mark the location of the tumor and to guide the biopsy needle in a vertical path. The laser beam source is movable in orthogonal paths while compensating means redirect the beams to maintain them within a target area or eliminate any parallax. That is, the angular position of the laser light beam is adjusted to different angles at different coordinate positions to have the needle follow along a portion of a straight line path from the X-ray point source through the lesion and to the X-ray film. Thus, the needle tip should not be displaced to one side of a small lesion.
Such prior art systems and methods have disadvantages. For instance, they are difficult to accurately and quickly calibrate. An improved targeting system and method of targeting is disclosed in pending U.S. patent application Ser. No. 09/792,191 filed Feb. 22, 2001 entitled “Targeting System And Method Of Targeting” and assigned to the assignee of the present invention, the disclosure of which is hereby incorporated by reference.